Transit concrete mixer



30, 1941. H. c. PET-ERS ETAL TRANSIT CONCRETE MIXER Filed Aug. 14, 1939s Sheefs-Sheet 1 mm Mm l lnwnn 1 l l I I I 1 J I I I I l I I I 1 I 1 I Xhm H. c. PETERS ETAL 2,267,801

' TRANSIT CONCRETE MIXER Dec. 30, 1941.

Filed Aug. 14, 1939 3 Sheets-Sheet 2 Patented Dec. 30, 1941 UNITED,STATE TRANSIT CONCRETE MIXER Harry (J. Peters and Harold E.

wood, Wis, assignors to The T. L.

Smith, Shore- Smith Company, Milwaukee, Wis, a corporation oi WisconsinApplication August 14, 1939, Serial No. 290,110

9 Claims.

This invention relates to concrete mixers, and refers particularly tothe so-called truck mixers or transit mixers wherein a mixing drum isrotatably mounted onan automobile truck chassis.

' introducing the water have been tried, but in-- variably it wasdifficult, if not impossible, to keep the discharge nozzle open andunobstructed at all times.

This invention therefore has as one of its objects to provide animproved manner of introdducing water into the batch whereby the wateris uniformly and quickly distributed throughout the entire batch, and insuch a manner that his impossible for concrete or grout to come incontact with the discharge nozzle.

Another object of this invention is to provide means for introducingwater into the drum under substantial pressure to thereby insure a moreuniform and faster distribution of water in the batch.

Another object of this invention is to provide an improved andsimplified manner of closing or sealing the open end of the mixing drum.

In this connection, it is a further object, of the invention to providea combined charging hopper and sealing door movably mounted adjacent theopen elevated end of the rotatable mixing drum to be swung toward andfrom the drum by a conveniently operated manual actuator.

Another object of this invention is to provide a combined charginghopper and sealing door for the purpose described, wherein that portionof the door which contacts the drum is freely rotatable, and whereinfree rotation is insured through the provision of an adequate lubricatedconnection between the rotatable and nonrotatable portions of the door.

Another object of this invention is to provide an improved manner ofmounting the distributing chute so that it is at times instantly readyfor use.

will appear as the description proceeds, this invention resides in thenovel construction, combination and arrangement of parts substantiallyas hereinafter described, and more particularly defined by the appendedclaims, it being understood that such changes in the precise embodimentof the hereindisclosed invention may be made as come withinthe scope ofthe claims.

The accompanying .drawings illustrate one complete example of thephysical embodiment of the invention, constructedin accordance with thebest mode so far devised for the practical application of the principlesthereof, and in which:

Figure 1 is a view in side elevation of a truck mixer embodying thisinvention; Figure 2 is a side view of the combined charging hopper andsealing door. with parts broken away and in section;

Figure 3 is a sectional view taken through Figure 2 on the plane of theline 3-3;

Figure 4 is an enlarged detail view illustrating the manner in which thenonrotatable and rotatable portions of the sealing door are connected;and

Figure 5 is a perspective view showing the rear end of a truck mixer toillustrate particularly the manner in which the materials expelled fromthe mixing drum enter the distributing chute.

Referring now to the accompanying drawings in which like numeralsindicate like parts, the numeral 5 designates the chassis of aconventional automobile truck or other suitable vehicle upon which amixing drum 6 is rotatably mounted with its axis inclined, as moreparticularly described in the aforementioned Adolph W. Rybeck Patent No.2,029,126.

The drum may be driven from the power plant of the truck or a separatepower plant I may be provided. In either instance, suitable transmissionmechanism is provided to permit the drum to be rotated in bothdirections.

The elevated rear end of the drum is open, and the charging as well asthe discharging of the drum is effected through this open end. When thedrum revolves in one direction, its blades (not shown) produce themixing action, and when the drum revolves in the opposite direction, thesame blades, being arranged spirally, act as conveyers to carry theconcrete upwardly to the open rear end of the drum.

Inasmuch as it is desirable to close the drum air, the open rear end ofthe drum is adapted to Withthe above and other objects in view which besubstantially closed by a combined charging hopper and sealing door,indicated generally by the numeral 8. This unit is pivotally mounted ona frame 9 carried by the chassis of the truck and including two uprightsidewise spaced supports, one on each side of. the drum.

The charging hopper per se comprises a funnel-like hopper Ill having anopen top and having its discharge spout pointing down into the drum whenin its normal position. The hopper I is hung on a transverse shaft Hjournalled in bearings carried by the upper ends of the upstanding sidemembers of the frame 9. Brackets l2 fixed to the shaft II are secured tothe sides of the hopper to provide the actual connection between theshaft and the hopper. Being thus secured non-rotatably to the shaft II,it follows that by rocking the shaft, it is possible to swing the hoppertoward and from the open end of the mixing drum.

Such swinging movement is conveniently effected by means of a screw l3rotatably but nonlongitudinally movably joumalled in a hearing itcarried by the frame 9. The screw l3 threads into a sleeve or tube IS,the upper end of which is connected with the outer end of a lever 16fixed to the shaft II. The lower end of the screw l3 carries a crank orother suitable'actuator l1.

Encircling and secured to the lower discharge end l8 of the hopper I0 isa disc-like plate 19. The outer diameter of this plate is less than thediameter of the open end of the drum, and the space therebetween isspanned by a rotatable ring 20 which engages the periphery of the drumopening so that the drum opening'is closed except for the restrictedpassage through the charging hopper.

To freely rotatably mount the ring 20, which may be of one piece or oflaminated construction, as shown, from the plate l8, two ring members 2|are clamped to opposite sides of the plate with their outer portionsextending beyond the margin of the plate to define an annular passagewayor .channel in which the adjacent inner peripheral edge portion of thering 20 is received.

The space between the ring members 2| is a bit greater than thethickness of the ring 20 so that free rotation of the ring 20 ispermitted and a lubricant receptacle is provided. Heavy grease or othersuitable lubricant may be injected into this receptacle through a port22 (see Figure 4), ,which may be closed by a suitable plug or grease gunfitting (not shown).

'ring 20. With this construction, the ring revolves freely with the drumwhen the combined charging hopper and sealing door are in their loweredclosed position, and as the screw 13 is rotated, the combined charginghopper and sealing door is readily swung to an open position, indicatedin dotted lines in Figure 5, permitting the discharge of the drumcontents.

One of the important features of the invention resides in the manner inwhich the water is introduced into the mixing drum. This is effectedthrough the provision of a water passage 25 formed in the charginghopper with its inlet 26 at one side of the hopper and its outletprovided with an injection nozzle 21 pointed toward the closed front endof the drum.

As best shown in Figures 2 and 3, this nozzle is positioned above thepath of the dry aggregates entering the drum through the charging hopperand is so located that concrete or grout will never contact the mouth ofthe nozzle. The objections of past constructions are thus entirelyobviated with this improved manner of introducing the water.

Water is conducted to the inlet 23 of the passage 25 from a measuringtank 28, under pressure. For this purpose the water measuring tank isconnected through a pipe line 29 with a force pump 30 driven from thepower plant I, and the discharge of the pump is connected through a pipeline 3| and a flexible hose 32 with the inlet 26 of the water passage. Avalve 29 controls the flow of water to the pump, and the flexible hose32 enables swinging movement of the combined charging hopper and sealingdoor.

Inasmuch as the water is introduced into the drum at substantialpressure, it will be readily apparent to those skilled in the art thatfaster and more uniform distribution of the water through the batch isobtained.

For discharging the mixed concrete, a, dictributing chute 33 isprovided. This chute is permanently pivotally mounted on a bracket 34carried by the frame 9 and positioned beneath the elevated rear end ofthe drum. The bracket 34 has two vertically spaced bearings 35 in whicha vertical shaft is mounted, this shaft having the distributing chutehung thereon. The upper end of the chute is thus at all times inposition to receive mixed concrete from the elevated rear end of thedrum.

To guide the discharging drum contents to the chute, a funnel-likecollar 36 embraces the lower edge of the opening in the mixing drum.This collar of course is supported from the stationary structure anddoes not turn with the drum.

The distributing chute 33 preferably comprises two hingedly connectedsections which are folded upon each other, as shown in Figure 5, duringtransit; and the angle of inclination of the chute is readily adjustablethrough the medium of a link 31 which supports the lower end of 'itsupper section, as clearly shown in Figure 5.

From the foregoing description taken in connection with the accompanyingdrawings, it will be readily apparent that this invention provides atruck mixer having many advantages over past constructions, and that itparticularly improves the manner of introducing water into the batch andthus insures more efficient operation.

What we claim as our invention is:

1. In a transit mixer, the combination of: a mixing drum rotatable on afixed axis and having a single opening through which the drum is chargedand discharged; a combined charging hopper and sealing door; meansmovably mounting said combined charging hopper and sealing door forbodily movement from a position spaced from the opening in the drum toallow the discharge of the drum contents through said opening to. aposition at which the door closes the opening of the drum and the hopperis operable and out of the path of material entering the drum; a sourceof water under pressure; and

means connecting said source with the water pas sage, part of saidconnecting means being flexible to allow free movement of the combinedcharging hopper and scaling door.

2. In a concrete mixer: a rotatable mixing drum having an open endthrough which the drum is charged and discharged;-a charging hopper; astationary frame movably mounting the charging hopper adjacent to saidopen end of the drum for movement to and from a position' directingaggregates into the drum; and a sealing ring encircling the dischargeend of the charging hopper and rotatably carried thereby in a positionto be engageable with the periphery of the drum opening when the hopperis in its charging position to direct aggregates into the drum.

3. In a concrete mixer: a rotatable mixing drum having an open endthrough which the drum is charged and discharged; a charging hopper; astationary frame movably mounting the charging hopper adjacent to saidopen end of the drum for movement to and from a position directingaggregates into the drum; a

sealing ring encircling the discharge end of the charging hopper androtatably carried thereby in a position to be engageable with theperiphery of the drum opening when the hopper is in its. chargingposition to direct aggregates into the drum; and means carried by thecharging hopper for introducing water into the interior of the drum.

4. In a. concrete mixer: a rotatable mixing drum having an open endthrough which the I drum is charged and discharged; a charging hopper;means mounting the charging hopper for movement to and from a chargingposition directing materials into the drum through its open end; a.disc-like plate carried by the charging hopper; and a ring encirclingthe charging hopper and rotatably mounted on said plate in a position tobe engageable with the periphery of the opening in the drum when thehopper is in its charging position, whereby said ring and plate closethe open end of the drum and the ring revolves with the drum around thehopper.

5. In a concrete mixer: a rotatable drum having an open end; a charginghopper; means-pivotally mounting the charging hopper adjacent to a theopen end of the drum; means carried by the charging hopper and formingan annular guideway; and a ring freely rotatable in said annularguideway and engageable with the periphery of the drum opening when thecharging hopper is z at whichfthe discharge end of the hopper directslmatgirialinto the celgyated QDQXlfiild Of the drum;

' a" flange encircling tr e discharge e'nd'of the charging hopper; asealingqring interposed between the peripheryof the open'end of the drumandsaid flange, when-the charginghoppe'risin its charging position,said. ring being freely rotatable with respect to the flange so'as" toturn with the drum; and means: for; swingingzthe-v charging hopperupwardly away from the open end of the drum to enable discharge of thedrum'contents.

8. Ina truck mixer otthe character described: a drum rotatably mountedon an inclined axis and having its rear elevated end open; a charginghopper; a stationary frame pivotally mounting the charging hopper toswing toward and from the elevated open end of the drum; a sealingmember carried by the charging hopper and engageable with the peripheryof the open end of the drum when the charging hopper is in its loweredposition; means for swinging the charging hopper upwardly away from theopen end of the drum-to enable discharge of the drum contents, saidmeans including a screw adapted to be manually rotated; and a. partconnected with the charging hopper and having'threaded engagement withthe screw.

9. In a truck mixer having a frame and a power plant, the combinationof: a. drum mounted in the frame 'for rotation on a fixed axis andadapted to be driven by the power plant, said drum being chargeable anddischargeable through one open end; a combined charging hopper andclosure; means for movably mounting said combined charging hopper andclosure from the frame adjacent to the openend of the drum for movementfrom an operative charging position at which the hopper directsaggregates into the drum and the space between the hopper and theperiphery of the open end of the drum is closed, to an inoperativeposition out of the path of material discharged from the open end of thedrum; a water injection nozzle carried by the combined charging hopperand closure for introducing water into the interior of the drum; saidwater injection nozzle being fixed with relation to the combinedcharging hopper and closure in a position such that its discharge end isspaced outwardly a substantialdistance from the discharge end of thecharging hopper and out of the path of material entering the drum whenthe charging hopper is in an operative charging position; a water pumpdriven by the power plant; and means for connecting the outlet of thepump with said water injection nozzle, part of said means being fixedwith respect to the frame and part thereof being movable to accommodatemotion of the combined charging hopper and closure with respect to thedrum.

HARRY C. PETERS.

HAROLD E. SMITH.

oE RTIFIcATh OF CORREC'TION. Y

l. v 1 V Deeember 5o, 19L 1Q M I f, "l: HARRY c. PETERS, ET AL.

that errorappeure in the printed seoifioetio'n r-of g e aobv u beredpatent requiring correction as follows;

ll jy 811m 4- strike out the words "F; 5 h'f l sarneflaftr' drum" in.lirie he,

P at ent should he" read with this go fthe r eciorduof the case in thPage 5,'f 1rs t around the hopper" and 1hsame claim; and; that the sai dLetrrection therein that the seam e Patent Office. signed and sealedthis 17th day of February, A D. l9h2.

e may Henry Van Arsdale,

Acting; Commissioner 1 Palzonls.

